The prostate gland has the unique function of accumulating and secreting high levels of citrate, and testosterone is a major regulator of citrate production by the gland. Citrate production is very high in benign prostate hyperplasia (BPH), and is very low in prostate carcinoma (CA). The proposed studies seek to establish the relationships of hormone regulation of prostate citrate production, to elucidate the mechanisms by which hormones regulate prostatic citrate production, and to apply these insights to address the pathogenesis of BPH and prostatic CA. The two enzymes most directly involved in the regulation of citrate production are mitochondrial aspartate aminotransferase (mAAT) and pyruvate dehydrogenase (PDH). Both enzymes are induced by testosterone. Using rat prostate as the tissue source, the proposed studies will address the role of testosterone in the regulation of the mAAT and PDH E1a genes by characterizing androgen response elements and the factors involved in cell specific response to testosterone in prostate epithelial cells.